Computational analysis of on-line coupled ITP-CE

摘要

Coupling isotachophoresis (ITP) to capillary elec-trophoresis (CE) has many benefits, but also introduces non-idealities into the concentrated sample. These non-idealities arise because of the interaction between the sample in the main flow channel and the pool of leading electrolyte in the side-arm. A computational model of the switching process was developed using FIDAP (Fluent Inc., Lebanon, NH). This paper presents a qualitative look at the asymmetries that arise during the switching process. Additionally, a control mechanism based on the time-derivative of voltage is also presented. This provides the user with real-time detection of the sample band as it passes the side-arm, and a means for implementing an automated switching strategy.